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1.
Both ions of the title compound, [Au(C4H8S)2](C6H4NO4S2), display crystallographic twofold symmetry. The Au atom exhibits linear coordination, with Au—S = 2.2948 (14) Å and S—Au—S = 178.47 (9)°. The crystal packing consists of layers of anions connected by C—H?O hydrogen bonds; the cations occupy cavities in these layers and the ions are linked by Au?N contacts of 3.009 (7) Å. Further C—H?O interactions connect the layers.  相似文献   

2.
In the title compound, [Ni(C2H3OS)2(C18H15P)2], the Ni atom lies on an inversion centre and the tri­phenyl phosphine and thio­acetate ligands are bonded to the central NiII atom in a trans fashion, with Ni—S = 2.2020 (8) and Ni—P = 2.2528 (8) Å, and angle S—Ni—P = 92.47 (3)°.  相似文献   

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The title compounds are salts of the general form (Q+)2[Zn(dmit)2]2?, where dmit corresponds to the ligand (C3S5)? present in both and Q+ to the counter‐cations (nBu4N)+ [or C16H36N+] and (Ph4As)+ [or C24H20As+], respectively. In the first case, Zn is in the 4e special positions of space group C2/c and hence the [Zn(dmit)2]2? dianion possesses twofold axial crystallographic symmetry. Including these, there are now 11 known examples of [Zn(dmit)2]2? or its analogues, with O replacing the exocyclic thione S, and [Zn(dmio)2]2? dianions in nine structures with various Q. Comparison of these reveals a remarkable variation in details of the conformation which the dianion may adopt in terms of Zn coordination, equivalence of the Zn—S bond lengths, displacement of Zn from the plane of the ligand and overall dianion shape.  相似文献   

8.
To create a novel vector for specifically delivering anticancer therapy to solid tumors, we used diafiltration to synthesize pH‐sensitive polymeric micelles. The micelles, formed from a tetrablock copolymer [poly(ethylene glycol)‐b‐poly(L ‐histidine)‐b‐poly(L ‐lactic acid)‐b‐poly(ethylene glycol)] consisted of a hydrophobic poly(L ‐histidine) (polyHis) and poly(L ‐lactic acid) (PLA) core and a hydrophilic poly(ethylene glycol) (PEG) shell, in which we encapsulated the model anticancer drug doxorubicin (DOX). The robust micelles exhibited a critical micellar concentration (CMC) of 2.1–3.5 µg/ml and an average size of 65–80 nm pH 7.4. Importantly, they showed a pH‐dependent micellar destabilization, due to the concurrent ionization of the polyHis and the rigidity of the PLA in the micellar core. In particular, the molecular weight of PLA block affected the ionization of the micellar core. Depending on the molecular weight of the PLA block, the micelles triggering released DOX at pH 6.8 (i.e. cancer acidic pH) or pH 6.4 (i.e. endosomal pH), making this system a useful tool for specifically treating solid cancers or delivering cytoplasmic cargo in vivo. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

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The structure of the title compound, [Ca(C10H15O4S)2(H2O)4], is the first example in which two d ‐camphor‐10‐sulfonate anions are coordinated to a metal ion, in this case with direct Ca—O bonding. The molecule has crystallographically imposed twofold symmetry with the Ca atom on the twofold axis. Hydrogen bonds are formed between the coordinated water molecules and the O atoms of the SO3 groups of adjacent molecules, leading to the formation of a two‐dimensional layered network. The compound displays sharp wavelength‐selective transparency in the UV–visible spectrum, offering the potential for application as an optical filter.  相似文献   

11.
《化学:亚洲杂志》2017,12(22):2929-2941
In contrast to diradicals connected by alternant hydrocarbons, only a few studies on those connected by nonalternant hydrocarbons have been reported. The syntheses, structures, and magnetic properties of azulene‐1,3‐diyl linked bis(nitronyl nitroxide) (NN2Az) and bis(iminonitroxide) (IN2Az) diradicals and their Cu(hfac)2 (hfac=hexafluoroacetylacetonate) complexes were investigated. NN2Az was shown to have an intramolecular ferromagnetic interaction with J obs/k B=+10.0 K (H =−2J S 1 ⋅S 2) between (nitronyl nitroxide) spins, whereas IN2Az was estimated to have a much weaker intramolecular magnetic interaction. The reactions of NN2Az and IN2Az with Cu(hfac)2 gave a 1:2 [{Cu(hfac)2}2(NN2Az)] complex and a 1:1 [Cu(hfac)2(IN2Az)] ⋅ C6H12 complex, respectively. [{Cu(hfac)2}2(NN2Az)] showed strong intramolecular antiferromagnetic interactions (J 1‐Cu‐R/k B≈−800 K, J 2‐Cu‐R/k B≈−500 K) between the CuII spins and the coordinating NN spins, whereas [Cu(hfac)2(IN2Az)] exhibited a ferromagnetic exchange interaction (J obs‐Cu‐R/k B=+114 K) between the CuII spin and the imino‐coordinated iminonitroxide spin.  相似文献   

12.
Tetrakis(diethyl phosphonate), Tetrakis(ethyl phenylphosphinate)‐, and Tetrakis(diphenylphosphine oxide)‐Substituted Phthalocyanines The title compounds 7, 9 , and 11 are obtained by tetramerization of diethyl (3,4‐dicyanophenyl)phosphonate ( 5 ), ethyl (3,4‐dicyanophenyl)phenylphosphinate ( 8 ), and 4‐(diphenylphosphinyl)benzene‐1,2‐dicarbonitrile ( 10 ). The 31P‐NMR spectra of the phthalocyanines 7, 9 , and 11 and of their metal complexes present five to eight signals confirming the formation of four constitutional isomers with the expected C4h, D2h, C2v, and Cs symmetry. In the FAB‐MS of the Zn, Cu, and Ni complexes of 7 and 9 , the peaks of dimeric phthalocyanines are observed. By gel‐permeation chromatography, the monomeric complex [Ni( 7 )] and a dimer [Ni( 7 )]2 can be separated. These dimers differ from the known phthalocyanine dimers, i.e., possibly the P(O)(OEt)2 and P(O)(Ph)(OEt) substituents in 7 and 9 are involved in complexation. The free phosphonic acid complex [Zn( 12 )] and [Cu( 12 )] are H2O‐soluble. In the FAB‐MS of [Zn( 12 )], only the peaks of the dimer are present; the ESI‐MS confirms the existence of the dimer and the metal‐free dimer. In the UV/VIS spectrum of [Zn( 12 )], the hypsochromic shift characteristic for the known type of dimers from 660–700 nm to 620–640 nm is observed. As in the FAB‐MS of [Zn( 12 )], the free phosphinic acid complex [Zn( 13 )] shows only the monomer, an ESI‐MS cannot be obtained for solubility problems. The UV/VIS spectrum of [Zn( 13 )] demonstrates the existence of the monomer as well as of the dimer.  相似文献   

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The three title compounds tri‐μ‐carbonyl‐1:2κ2C;1:3κ2C;2:3κ2C‐octacarbonyl‐1κC,2κ2C,3κ2C,4κ3C‐η5‐methylcyclopentadienyl‐tetrahedro‐triiridiummolybdenum(3 IrIr)(3 IrMo), tri‐μ‐carbonyl‐1:2κ2C;1:3κ2C;2:3κ2C‐octacarbonyl‐1κC,2κ2C,3κ2C,4κ3C‐η5‐tetramethylcyclopentadienyl‐tetrahedro‐triiridiummolybdenum(3 IrIr)(3 IrMo) and tri‐μ‐carbonyl‐1:2κ2C;1:3κ2C;2:3κ2C‐octacarbonyl‐1κC,2κ2C,3κ2C,4κ3C‐η5‐pentamethylcyclopentadienyl‐tetrahedro‐triiridiummolybdenum(3 IrIr)(3 IrMo), [MoIr35‐C5H5?nMen)(μ‐CO)3(CO)8], where n = 1, 4 or 5, have a pseudo­tetrahedral MoIr3 core geometry, with a η5‐C5H5?nMen group ligating the Mo atom, bridging carbonyls spanning the edges of an MoIr2 face, and eight terminally bound carbonyls.  相似文献   

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The step‐wise solution self‐assembly of double crystalline organometallic poly(ferrocenyldimethylsilane)‐block‐poly(2‐iso‐propyl‐2‐oxazoline) (PFDMS‐b‐PiPrOx) diblock copolymers is demonstrated. Two block copolymers are obtained by copper‐catalyzed azide‐alkyne cycloaddition (CuAAC), featuring PFDMS/PiPrOx weight fractions of 46/54 (PFDMS30b‐PiPrOx75) and 30/70 (PFDMS30b‐PiPrOx155). Nonsolvent induced crystallization of PFDMS in acetone leads in both cases to cylindrical micelles with a PFDMS core. Afterward, the structures are transferred into water for sequential temperature‐induced crystallization of the PiPrOx corona, leading to hierarchical double crystalline superstructures, which are investigated using scanning electron microscopy, wide angle X‐ray scattering, and differential scanning calorimetry.

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17.
The structure of the title complex consists of isolated [Cd(C7H4NO3S)2(C4H11NO2)2] units. The Cd2+ cation lies on an inversion centre and is octahedrally coordinated by two N,O‐bidentate diethanol­amine (dea) and two N‐bonded saccharinate (sac) ligands [saccharin is 1,2‐benziso­thia­zol‐3(2H)‐one 1,1‐dioxide]. The dea ligands constitute the equatorial plane of the octahedron, forming two five‐membered chelate rings around the CdII ion, while the sac ligands are localized at the axial positions. The Cd—Nsac, Cd—Ndea and Cd—Odea bond distances are 2.3879 (12), 2.3544 (14) and 2.3702 (13) Å, respectively. The H atoms of the free and coordinated hydroxyl groups of the dea ligands are involved in hydrogen bonding with the carbonyl and sulfonyl O atoms of the neighbouring sac ions, while the amine H atom forms a hydrogen bond with the free hydroxyl O atom. The individual mol­ecules are held together by strong hydrogen bonds, forming an infinite three‐dimensional network.  相似文献   

18.
The title compound, C8H17NO2, exists as a zwitterion, adopting a propeller conformation. Molecules self‐assemble to form a hydrogen‐bonded layer parallel to the ab crystallographic plane connected by N+—H...O and C—H...O hydrogen bonds. These layers are stacked along the c axis and are stabilized by van der Waals interactions.  相似文献   

19.
A novel macrocycle containing fluorescein, the highly fluorescent title compound, C31H32O5, has a xanthene core and a benzyl unit that are planar. The latter is rotated by 72.99 (3)° from the xanthene mean plane. The C11 alkyl tether and the xanthene group adopt a cage‐like structure and the xanthene adopts a quinoid‐type configuration. The compound crystallizes as a racemic mixture with one molecule of each isomer per unit cell. Even though the planes described by the xanthene and the benzene rings of different molecules are separated by 3.341 (4) and 3.73 (1) Å, respectively, there is insufficient overlap between the aryl units to promote π‐stacking.  相似文献   

20.
The crystal structures of tris(2‐methyl­quinolin‐8‐olato‐N,O)­iron(III), [Fe­(C10­H8­NO)3], (I), and aqua­bis(2‐methyl­quinolin‐8‐olato‐N,O)­copper(II), [Cu­(C10­H8NO)2­(H2O)], (II), have been determined. Compound (I) has a distorted octahedral configuration, in which the central Fe atom is coordinated by three N atoms and three O atoms from three 2‐methylquinolin‐8‐olate ligands. The three Fe—O bond distances are in the range 1.934 (2)–1.947 (2) Å, while the three Fe—N bond distances range from 2.204 (2) to 2.405 (2) Å. In compound (II), the central CuII atom and H2O group lie on the crystallographic twofold axis and the coordination geometry of the CuII atom is close to trigonal bipyramidal, with the three O atoms in the basal plane and the two N atoms in apical positions. The Cu—N bond length is 2.018 (5) Å. The Cu—O bond length in the basal positions is 1.991 (4) Å, while the Cu—O bond length in the apical position is 2.273 (6) Å. There is an intermolecular OW—H?O hydrogen bond which links the mol­ecules into a linear chain along the b axis.  相似文献   

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